In fact, the 62 year-old founder of Microsoft would would be worth more than $150 billion (£112.4bn) if he hadn't donated nearly $700 million (£524.91m) Microsoft Corp. shares and $2.9 billion (£2.17bn) of cash and other assets to charity since 1996. As pointed by the report, online sales increased by 18.4 percentage in comparison to past year as reported by Adobe Analytics.

Mr Bezos started Amazon in his basement in Seattle 22 years ago, after he quit his job as a hedge fund manager in NY.

Mr Gates is now second in the Index with $89,1bn, followed by Warren Buffet ($78.7bn) and Spain's Armancio Ortega ($75.9bn).

Bezos, who founded Amazon, owns about 78.9 million shares of the company, according to a November 14 filing.

Bezos, who surpassed Gates as the world's richest man in October, suggested he knew he needed to up his philanthropy earlier this year when he took to Twitter to ask for ideas.

He wrote: "I'm thinking I want much of my philanthropic activity to be helping people in the here and now - short term - at the intersection of urgent need and lasting impact".